1. Field of the Invention
This invention relates to nuclear reactors and protection of the public and, particularly, nuclear reactor containment structures which dissipate heat following an extremely low probability core meltdown and subsequent breach in the reactor vessel.
2. Background Discussion
Because of the radioactive materials contained in a nuclear reactor, great caution must be taken to prevent the escape of such materials to the environment. One type of nuclear reactor is the liquid metal fast-breeder reactor which employs a core immersed in liquid sodium coolant. If all heat removal capacity were lost, and temperatures within the reactor should exceed the melting point of the core, the core would disintegrate and core materials could reach the bottom of the reactor, where the debris layer heat generation rate could be sufficiently high to cause failure of the walls of the reactor vessel and guard vessel.
If this would occur both sodium and fragmented radioactive core debris would escape from the reactor vessel. The reactor containment must be designed to retain such radioactive materials which might penetrate the reactor vessel, and must prevent their entry into the environment where they can endanger public health and safety.
There is disclosed in U.S. patent application Ser. No. 800,566, filed Nov. 21, 1985 in the name of A. Hunsbedt, and J. D. Lazarus and entitled Heat Dissipating Nuclear Reactor, a novel reactor (herein referred to as Reactor I). This application disclosing Reactor I is incorporated herein by reference. The present invention provides an improvement in Reactor I.